Awaiting clinical review. This entry is sourced but has not yet been signed off by a pharmacist or clinician.

Ilex paraguariensis (leaf)

Yerba mate

Yerba mate is a caffeinated South American tea. It will feel stimulating for the reason coffee does, but we found no trial that tested mate for alertness itself, and reviews of its effect on cholesterol and weight are mostly null. The main caution is temperature: the World Health Organization's cancer agency classes drinking any beverage above 65 °C as probably causing oesophageal cancer, and mate is traditionally drunk at about 70 °C. Caffeine also matters for sleep, anxiety, heart rate and pregnancy.

Written by

Healthy and Herbal editorial team

Updated

29 September 2026

A mate gourd with a metal straw and loose yerba mate

At a glance

Last reviewed 29 September 2026

Evidence

Limited

Best for

Blood sugar in prediabetes

Typical form & use

Tea or capsules, about 3 g leaf a day

Onset

4+ weeks

Safety

Contains caffeine; drink below 65 °C. No interactions in our data.

Check with your medications →

What it's used for

Evidence is rated per use. The same ingredient can be strong for one thing and traditional for another.

Use	Evidence	What the research shows
Blood sugar in prediabetes	Limited	A 2025 meta-analysis of 13 randomised trials found that in people with prediabetes, mate lowered postprandial glucose (mean difference -12.76, 95% CI -16.78 to -8.74), HbA1c (-0.37, -0.56 to -0.18) and HOMA index (-0.24, -0.37 to -0.11). Each of these rests on only two trials, and fasting glucose and fasting insulin did not change overall. The authors say more research is needed.¹
Energy and alertness	Traditional	Mate contains caffeine, roughly 78–196 mg per 500 mL serving depending on preparation, and one 2025 review attributes its stimulating effects on alertness and mental fatigue to caffeine and theobromine. That review is narrative, and we did not find or read a controlled trial of mate for alertness. A 2023 systematic review reports benefits for mood and exercise performance but rates the certainty of evidence as moderate to very low and most included studies as high risk of bias. We rate this on the caffeine content and traditional use.^2,3
Body weight and body fat	Limited	One 12-week trial in 30 Korean adults with obesity, giving 3 g of mate capsules a day, found a greater fall in body fat mass and body fat percentage than placebo. The 2025 meta-analysis of 13 trials found no significant effect on waist circumference or BMI. Small trials, mixed results.^1,4
Cholesterol	Limited	A 2022 meta-analysis of 7 experimental studies (378 people) found no difference from control in total cholesterol (mean difference 6.4 mg/dl, 95% CI -2.2 to 15.0), LDL (5.5, -1.5 to 12.6), HDL or triglycerides. The 2025 meta-analysis agreed. Individual studies are conflicting, so the honest summary is that lipid lowering is not established.^1,5

How much

Ranges below are what studies used and what supplements commonly contain. They are not a recommendation for you. Start at the low end.

Studied range

About 3 g leaf a day^4,1

The one placebo-controlled weight trial we read gave 3 g of mate capsules a day for 12 weeks. Trials in the 2025 meta-analysis varied in dose, so this is not a proven optimum.

Caffeine per serving

About 78–196 mg per 500 mL²

Varies with leaf, cut and how it is brewed. Traditional daily intake of 1–2 L has been estimated at roughly 100–300 mg of caffeine.

Caffeine ceiling

400 mg a day for most adults⁶

The US FDA cites 400 mg a day from all sources as a safe amount for most adults, with individual sensitivity varying. Count coffee, tea and energy drinks too.

Serving temperature

Below 65 °C⁷

IARC defines 'very hot' as above 65 °C. Let it cool before drinking.

Timing · We found no source giving timing advice. Because of the caffeine, drinking it late in the day may disturb sleep; the FDA lists sleep disruption among the effects of too much caffeine.With food? · No source we read gave food guidance. Stomach upset is listed among reported adverse events in the 2025 meta-analysis.How long to trial · The glycaemic and body-fat findings came from trials lasting weeks to months, so a few days will not tell you anything about them. The stimulating effect of the caffeine itself is felt within hours.

How people take it

Loose leaf infusion (gourd or French press)Up to 500 mL or more per servingThe traditional way. Refilling the vessel raises the total caffeine; one estimate puts 500 mL at 78–196 mg or more.

Tea bagOne bag per cupA tea-bag cup is usually a smaller serving, but we did not find a source for typical bag caffeine content.

Capsule (leaf powder)3 g a day in one trialThe form used in the 12-week weight trial. Capsule products vary, so check the label for caffeine.

Safety

Who should avoid

Very hot mate — drink below 65 °C; IARC links very hot drinks to oesophageal cancer
Pregnancy and breastfeeding — ask your clinician about limiting caffeine
Sensitivity to caffeine — palpitations, anxiety and poor sleep
Heart rhythm problems or high blood pressure — caffeine raises heart rate and pressure
Smokers and heavy drinkers — cancer risks from mate add to theirs (IARC notes both cause it)

Known interactions

No interactions in our data. Absence of a flag is not clearance.

Questions people ask

Does yerba mate have as much caffeine as coffee?

Usually somewhat less per serving. One 2025 review puts mate at about 78–196 mg per 500 mL, against roughly 95–200 mg for a 240 mL cup of filtered coffee. Strength varies a lot with brewing, and refilling the gourd raises your total.

Does yerba mate cause cancer?

IARC (2016) found drinking mate at temperatures that are not very hot could not be classified as to carcinogenicity, but drinking any very hot beverage (above 65 °C) is probably a cause of oesophageal cancer, and traditional mate is drunk at about 70 °C. A 2018 meta-analysis found raised odds of upper aerodigestive tract cancer with mate regardless of temperature (OR 2.24), so the two sources do not fully agree; letting it cool is sensible either way.

Will yerba mate help me lose weight or lower cholesterol?

Not reliably. A 2022 meta-analysis found no change in cholesterol or triglycerides, and a 2025 meta-analysis found no effect on BMI or waist circumference. One small 12-week trial found modest falls in body fat.

Is yerba mate safe every day?

A 12-week trial reported no clinically significant safety changes, though the 2025 meta-analysis listed insomnia, tachycardia, angina, headache and stomach upset as adverse events. Keep total caffeine under about 400 mg a day, and note that long-term safety of heavy daily use is not established by the trials we read.

Sources

Last reviewed 29 September 2026 · Next review March 2027 · How we rate evidence